1. Field of the Invention
The present invention relates to an ultrasonic image processing apparatus and the like which can dynamically track a target locomotive tissue by using, for example, MPR images typified by C-mode tomograms in accordance with the motion of the tissue, and display, in a predetermined form, the motion information of the tissue computed by using the tracking result.
2. Description of the Related Art
An ultrasonic diagnosis technique can display, in real time, how a heart beats or a fetus moves, with simple operation of bringing an ultrasonic probe into contact with the body surface. In addition, this technique offers a high level of safety, and hence can be repeatedly used for examination. Furthermore, the system size is smaller than those of other diagnosis apparatuses such as X-ray, CT, and MRI apparatuses. Therefore, this apparatus allows easy examination upon being moved to a bed side. That is, the apparatus is a convenient diagnosis technique. Ultrasonic diagnosis apparatuses used in such ultrasonic diagnosis vary depending on the types of functions which they have. Some of compact apparatuses which can be carried with one hand have been developed. Ultrasonic diagnosis is free from the influence of radiation exposure such as X-ray exposure, and hence can be used in obstetric treatment, treatment at home, and the like.
It is very important for tissue diagnosis to objectively and quantitatively evaluate the function of a living tissue such as myocardial by using such an ultrasonic diagnosis apparatus. For example, as disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2003-175041, there has recently been available, as a quantitative evaluation method for the heart, a technique of calculating local myocardial wall motion information such as displacement or strain while performing local pattern matching in images. Likewise, as disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2003-175041, there is available a technique of accurately computing the three-dimensional distribution of myocardial wall motion information by using an ultrasonic diagnosis apparatus capable of acquiring three-dimensional images. These techniques can acquire three-dimensional myocardial wall motion information and quantitatively evaluate the function of a tissue.
In addition, there has recently been developed a technique of more specifically analyzing acquired three-dimensional motion information and displaying the resultant information in a predetermined form. For example, there is available a technique of calculating local myocardial wall motion information with respect to an arbitrary slice (MPR) image of dimensional data. In addition, as disclosed in Philips “iSlice View” QLAB's 3DQ Advanced plug-in features: Provides 9 equally-spaced MPR short axis views between the LV mitral annulus and apex (http://www.medical.philips.com/main/products/ultrasoud/general/qlab/features/3dq_advanced/index.html), a technique of acquiring transverse slice (C-mode) images of a left ventricle at a plurality of positions (e.g., nine positions) and displaying them side by side has been put into practice.
The following problems arise in the conventional method of analyzing three-dimensional motion information.
A conventional apparatus analyzes three-dimensional motion information by using MPR images at a temporally constant position (e.g., a plane whose position does not change with time). On the other hand, the myocardial generally moves while deforming in a complex manner. For this reason, the conventional technique cannot implement chronological observation of locally the same region (tissue). For example, the heart shortens in the long axis direction. If a constant slice is continuously observed by the conventional technique using C-mode images as short-axis images, pieces of different information in the long axis direction are sequentially replaced with each other with time.
In addition, the conventional apparatus displays nine C-mode images to cover an entire three-dimensional area as an observation target. As a result, the number of images to be observed becomes large, and hence it is difficult for an observer to simultaneously grasp all images. Furthermore, since a display range is generally limited, the display size per image decreases. This makes it difficult to observe a fine abnormal region.